2007 - 2008 Texas Influenza Surveillance Information

Influenza Surveillance Report for MMWR Week 52

The influenza (flu) activity level for Texas for the week ending December 29, 2007 is “regional.” Regional activity indicates that two or more but less than half of the regions in the state are experiencing an increase in influenza-like illness (ILI) and have recent culture–confirmed influenza.

Reports were received from all 11 Health Service Regions for week 52. HSRs 2/3, 7, and 9/10 reported an increase in flu activity from the previous week. For a map of Health Service Regions, please visit the following website:

During week 52, six hospital laboratories throughout Texas and the Texas Department of State Health Services Laboratory reported conducting a total of 1,631 influenza tests (antigen, culture, and PCR) to the National Respiratory and Enteric Virus Surveillance System (NREVSS ) sponsored by the Centers for Disease Control and Prevention (CDC). Seventeen antigen detection tests positive for influenza A/untyped were reported from Bexar, Collin, and Harris counties; Harris County also reported one antigen detection test positive for influenza B. No PCR results were reported through NREVSS, but PCR tests positive for influenza A/untyped were reported for Brazos and Coryell counties by another source. A total of 21 reports of culture–confirmed influenza were received from NREVSS and other sources for the following counties:

Influenza A/H1

Influenza A/H3

Influenza A/untyped

Influenza B

El Paso County

Erath County

Bell County (7)

Cherokee County

Hemphill County

Starr County (4)

Brazos County

Harris County

Dallas County

Grimes County

Harris County (2)

The Air Force Institute for Operational Health (AFIOH) did not report any positive cultures for influenza virus collected from Texas bases in week 52. Additional positive results from point–of–care rapid flu tests were reported by providers throughout the state (see Texas map below).

No institutional outbreaks or school closures were reported for week 52.

Sixty–seven sentinel providers reported data to the U.S. Influenza Sentinel Provider Surveillance System (SPSN) on patients with influenza–like illness (ILI) and total patients seen for any reason during week 52. Sixty providers reported seeing patients during week 52; of those, 36 (60%) providers reported seeing at least one patient with ILI. Of all patient visits during this week, 4.93% were due to ILI. The ILI baseline for the West South Central Region (Arkansas, Louisiana, Oklahoma, and Texas) of the United States is 4.3% for the 2007–2008 season. The baseline is the mean percentage of patient visits for ILI during non–influenza weeks for the previous three seasons plus two standard deviations.

Percentage of Influenza–Like Illness (ILI) Reported by Sentinel Providers in Texas as of (1/8/2008 7:32:28 PM)